[deliverable/linux.git] / arch / m68k / kernel / process.c

/*
 *  linux/arch/m68k/kernel/process.c
 *
 *  Copyright (C) 1995  Hamish Macdonald
 *
 *  68060 fixes by Jesper Skov
 */

/*
 * This file handles the architecture-dependent parts of process handling..
 */

#include <linux/errno.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/smp.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/reboot.h>
#include <linux/init_task.h>
#include <linux/mqueue.h>

#include <asm/uaccess.h>
#include <asm/traps.h>
#include <asm/machdep.h>
#include <asm/setup.h>
#include <asm/pgtable.h>


asmlinkage void ret_from_fork(void);


/*
 * Return saved PC from a blocked thread
 */
unsigned long thread_saved_pc(struct task_struct *tsk)
{
	struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp;
	/* Check whether the thread is blocked in resume() */
	if (in_sched_functions(sw->retpc))
		return ((unsigned long *)sw->a6)[1];
	else
		return sw->retpc;
}

/*
 * The idle loop on an m68k..
 */
static void default_idle(void)
{
	if (!need_resched())
#if defined(MACH_ATARI_ONLY)
		/* block out HSYNC on the atari (falcon) */
		__asm__("stop #0x2200" : : : "cc");
#else
		__asm__("stop #0x2000" : : : "cc");
#endif
}

void (*idle)(void) = default_idle;

/*
 * The idle thread. There's no useful work to be
 * done, so just try to conserve power and have a
 * low exit latency (ie sit in a loop waiting for
 * somebody to say that they'd like to reschedule)
 */
void cpu_idle(void)
{
	/* endless idle loop with no priority at all */
	while (1) {
		while (!need_resched())
			idle();
		schedule_preempt_disabled();
	}
}

void machine_restart(char * __unused)
{
	if (mach_reset)
		mach_reset();
	for (;;);
}

void machine_halt(void)
{
	if (mach_halt)
		mach_halt();
	for (;;);
}

void machine_power_off(void)
{
	if (mach_power_off)
		mach_power_off();
	for (;;);
}

void (*pm_power_off)(void) = machine_power_off;
EXPORT_SYMBOL(pm_power_off);

void show_regs(struct pt_regs * regs)
{
	printk("\n");
	printk("Format %02x  Vector: %04x  PC: %08lx  Status: %04x    %s\n",
	       regs->format, regs->vector, regs->pc, regs->sr, print_tainted());
	printk("ORIG_D0: %08lx  D0: %08lx  A2: %08lx  A1: %08lx\n",
	       regs->orig_d0, regs->d0, regs->a2, regs->a1);
	printk("A0: %08lx  D5: %08lx  D4: %08lx\n",
	       regs->a0, regs->d5, regs->d4);
	printk("D3: %08lx  D2: %08lx  D1: %08lx\n",
	       regs->d3, regs->d2, regs->d1);
	if (!(regs->sr & PS_S))
		printk("USP: %08lx\n", rdusp());
}

/*
 * Create a kernel thread
 */
int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{
	int pid;
	mm_segment_t fs;

	fs = get_fs();
	set_fs (KERNEL_DS);

	{
	register long retval __asm__ ("d0");
	register long clone_arg __asm__ ("d1") = flags | CLONE_VM | CLONE_UNTRACED;

	retval = __NR_clone;
	__asm__ __volatile__
	  ("clrl %%d2\n\t"
	   "trap #0\n\t"		/* Linux/m68k system call */
	   "tstl %0\n\t"		/* child or parent */
	   "jne 1f\n\t"			/* parent - jump */
#ifdef CONFIG_MMU
	   "lea %%sp@(%c7),%6\n\t"	/* reload current */
	   "movel %6@,%6\n\t"
#endif
	   "movel %3,%%sp@-\n\t"	/* push argument */
	   "jsr %4@\n\t"		/* call fn */
	   "movel %0,%%d1\n\t"		/* pass exit value */
	   "movel %2,%%d0\n\t"		/* exit */
	   "trap #0\n"
	   "1:"
	   : "+d" (retval)
	   : "i" (__NR_clone), "i" (__NR_exit),
	     "r" (arg), "a" (fn), "d" (clone_arg), "r" (current),
	     "i" (-THREAD_SIZE)
	   : "d2");

	pid = retval;
	}

	set_fs (fs);
	return pid;
}
EXPORT_SYMBOL(kernel_thread);

void flush_thread(void)
{
	current->thread.fs = __USER_DS;
#ifdef CONFIG_FPU
	if (!FPU_IS_EMU) {
		unsigned long zero = 0;
		asm volatile("frestore %0": :"m" (zero));
	}
#endif
}

/*
 * "m68k_fork()".. By the time we get here, the
 * non-volatile registers have also been saved on the
 * stack. We do some ugly pointer stuff here.. (see
 * also copy_thread)
 */

asmlinkage int m68k_fork(struct pt_regs *regs)
{
#ifdef CONFIG_MMU
	return do_fork(SIGCHLD, rdusp(), regs, 0, NULL, NULL);
#else
	return -EINVAL;
#endif
}

asmlinkage int m68k_vfork(struct pt_regs *regs)
{
	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0,
		       NULL, NULL);
}

asmlinkage int m68k_clone(struct pt_regs *regs)
{
	unsigned long clone_flags;
	unsigned long newsp;
	int __user *parent_tidptr, *child_tidptr;

	/* syscall2 puts clone_flags in d1 and usp in d2 */
	clone_flags = regs->d1;
	newsp = regs->d2;
	parent_tidptr = (int __user *)regs->d3;
	child_tidptr = (int __user *)regs->d4;
	if (!newsp)
		newsp = rdusp();
	return do_fork(clone_flags, newsp, regs, 0,
		       parent_tidptr, child_tidptr);
}

int copy_thread(unsigned long clone_flags, unsigned long usp,
		 unsigned long unused,
		 struct task_struct * p, struct pt_regs * regs)
{
	struct pt_regs * childregs;
	struct switch_stack * childstack, *stack;
	unsigned long *retp;

	childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;

	*childregs = *regs;
	childregs->d0 = 0;

	retp = ((unsigned long *) regs);
	stack = ((struct switch_stack *) retp) - 1;

	childstack = ((struct switch_stack *) childregs) - 1;
	*childstack = *stack;
	childstack->retpc = (unsigned long)ret_from_fork;

	p->thread.usp = usp;
	p->thread.ksp = (unsigned long)childstack;

	if (clone_flags & CLONE_SETTLS)
		task_thread_info(p)->tp_value = regs->d5;

	/*
	 * Must save the current SFC/DFC value, NOT the value when
	 * the parent was last descheduled - RGH  10-08-96
	 */
	p->thread.fs = get_fs().seg;

#ifdef CONFIG_FPU
	if (!FPU_IS_EMU) {
		/* Copy the current fpu state */
		asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory");

		if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2]) {
			if (CPU_IS_COLDFIRE) {
				asm volatile ("fmovemd %/fp0-%/fp7,%0\n\t"
					      "fmovel %/fpiar,%1\n\t"
					      "fmovel %/fpcr,%2\n\t"
					      "fmovel %/fpsr,%3"
					      :
					      : "m" (p->thread.fp[0]),
						"m" (p->thread.fpcntl[0]),
						"m" (p->thread.fpcntl[1]),
						"m" (p->thread.fpcntl[2])
					      : "memory");
			} else {
				asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t"
					      "fmoveml %/fpiar/%/fpcr/%/fpsr,%1"
					      :
					      : "m" (p->thread.fp[0]),
						"m" (p->thread.fpcntl[0])
					      : "memory");
			}
		}

		/* Restore the state in case the fpu was busy */
		asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0]));
	}
#endif /* CONFIG_FPU */

	return 0;
}

/* Fill in the fpu structure for a core dump.  */
#ifdef CONFIG_FPU
int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu)
{
	char fpustate[216];

	if (FPU_IS_EMU) {
		int i;

		memcpy(fpu->fpcntl, current->thread.fpcntl, 12);
		memcpy(fpu->fpregs, current->thread.fp, 96);
		/* Convert internal fpu reg representation
		 * into long double format
		 */
		for (i = 0; i < 24; i += 3)
			fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) |
			                 ((fpu->fpregs[i] & 0x0000ffff) << 16);
		return 1;
	}

	/* First dump the fpu context to avoid protocol violation.  */
	asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory");
	if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2])
		return 0;

	if (CPU_IS_COLDFIRE) {
		asm volatile ("fmovel %/fpiar,%0\n\t"
			      "fmovel %/fpcr,%1\n\t"
			      "fmovel %/fpsr,%2\n\t"
			      "fmovemd %/fp0-%/fp7,%3"
			      :
			      : "m" (fpu->fpcntl[0]),
				"m" (fpu->fpcntl[1]),
				"m" (fpu->fpcntl[2]),
				"m" (fpu->fpregs[0])
			      : "memory");
	} else {
		asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0"
			      :
			      : "m" (fpu->fpcntl[0])
			      : "memory");
		asm volatile ("fmovemx %/fp0-%/fp7,%0"
			      :
			      : "m" (fpu->fpregs[0])
			      : "memory");
	}

	return 1;
}
EXPORT_SYMBOL(dump_fpu);
#endif /* CONFIG_FPU */

/*
 * sys_execve() executes a new program.
 */
asmlinkage int sys_execve(const char __user *name,
			  const char __user *const __user *argv,
			  const char __user *const __user *envp)
{
	int error;
	char * filename;
	struct pt_regs *regs = (struct pt_regs *) &name;

	filename = getname(name);
	error = PTR_ERR(filename);
	if (IS_ERR(filename))
		return error;
	error = do_execve(filename, argv, envp, regs);
	putname(filename);
	return error;
}

unsigned long get_wchan(struct task_struct *p)
{
	unsigned long fp, pc;
	unsigned long stack_page;
	int count = 0;
	if (!p || p == current || p->state == TASK_RUNNING)
		return 0;

	stack_page = (unsigned long)task_stack_page(p);
	fp = ((struct switch_stack *)p->thread.ksp)->a6;
	do {
		if (fp < stack_page+sizeof(struct thread_info) ||
		    fp >= 8184+stack_page)
			return 0;
		pc = ((unsigned long *)fp)[1];
		if (!in_sched_functions(pc))
			return pc;
		fp = *(unsigned long *) fp;
	} while (count++ < 16);
	return 0;
}
Commit	Line	Data
fde39441 GU	1	/*
	2	* linux/arch/m68k/kernel/process.c
	3	*
	4	* Copyright (C) 1995 Hamish Macdonald
	5	*
	6	* 68060 fixes by Jesper Skov
	7	*/
	8
	9	/*
	10	* This file handles the architecture-dependent parts of process handling..
	11	*/
	12
	13	#include <linux/errno.h>
	14	#include <linux/module.h>
	15	#include <linux/sched.h>
	16	#include <linux/kernel.h>
	17	#include <linux/mm.h>
	18	#include <linux/slab.h>
	19	#include <linux/fs.h>
	20	#include <linux/smp.h>
	21	#include <linux/stddef.h>
	22	#include <linux/unistd.h>
	23	#include <linux/ptrace.h>
	24	#include <linux/user.h>
	25	#include <linux/reboot.h>
	26	#include <linux/init_task.h>
	27	#include <linux/mqueue.h>
	28
	29	#include <asm/uaccess.h>
fde39441 GU	30	#include <asm/traps.h>
	31	#include <asm/machdep.h>
	32	#include <asm/setup.h>
	33	#include <asm/pgtable.h>
	34
	35
	36	asmlinkage void ret_from_fork(void);
	37
	38
	39	/*
	40	* Return saved PC from a blocked thread
	41	*/
	42	unsigned long thread_saved_pc(struct task_struct *tsk)
	43	{
	44	struct switch_stack sw = (struct switch_stack )tsk->thread.ksp;
	45	/* Check whether the thread is blocked in resume() */
	46	if (in_sched_functions(sw->retpc))
	47	return ((unsigned long *)sw->a6)[1];
	48	else
	49	return sw->retpc;
	50	}
	51
	52	/*
	53	* The idle loop on an m68k..
	54	*/
	55	static void default_idle(void)
	56	{
	57	if (!need_resched())
	58	#if defined(MACH_ATARI_ONLY)
	59	/* block out HSYNC on the atari (falcon) */
	60	__asm__("stop #0x2200" : : : "cc");
	61	#else
	62	__asm__("stop #0x2000" : : : "cc");
	63	#endif
	64	}
	65
	66	void (*idle)(void) = default_idle;
	67
	68	/*
	69	* The idle thread. There's no useful work to be
	70	* done, so just try to conserve power and have a
	71	* low exit latency (ie sit in a loop waiting for
	72	* somebody to say that they'd like to reschedule)
	73	*/
	74	void cpu_idle(void)
	75	{
	76	/* endless idle loop with no priority at all */
	77	while (1) {
	78	while (!need_resched())
	79	idle();
b57cb723	80	schedule_preempt_disabled();
fde39441 GU	81	}
	82	}
	83
	84	void machine_restart(char * __unused)
	85	{
	86	if (mach_reset)
	87	mach_reset();
	88	for (;;);
	89	}
	90
	91	void machine_halt(void)
	92	{
	93	if (mach_halt)
	94	mach_halt();
	95	for (;;);
	96	}
	97
	98	void machine_power_off(void)
	99	{
	100	if (mach_power_off)
	101	mach_power_off();
	102	for (;;);
	103	}
	104
	105	void (*pm_power_off)(void) = machine_power_off;
	106	EXPORT_SYMBOL(pm_power_off);
	107
	108	void show_regs(struct pt_regs * regs)
	109	{
	110	printk("\n");
	111	printk("Format %02x Vector: %04x PC: %08lx Status: %04x %s\n",
	112	regs->format, regs->vector, regs->pc, regs->sr, print_tainted());
	113	printk("ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n",
	114	regs->orig_d0, regs->d0, regs->a2, regs->a1);
	115	printk("A0: %08lx D5: %08lx D4: %08lx\n",
	116	regs->a0, regs->d5, regs->d4);
	117	printk("D3: %08lx D2: %08lx D1: %08lx\n",
	118	regs->d3, regs->d2, regs->d1);
	119	if (!(regs->sr & PS_S))
	120	printk("USP: %08lx\n", rdusp());
	121	}
	122
	123	/*
	124	* Create a kernel thread
	125	*/
	126	int kernel_thread(int (fn)(void ), void * arg, unsigned long flags)
	127	{
	128	int pid;
	129	mm_segment_t fs;
	130
	131	fs = get_fs();
	132	set_fs (KERNEL_DS);
	133
	134	{
	135	register long retval __asm__ ("d0");
	136	register long clone_arg __asm__ ("d1") = flags \| CLONE_VM \| CLONE_UNTRACED;
	137
	138	retval = __NR_clone;
	139	__asm__ __volatile__
	140	("clrl %%d2\n\t"
	141	"trap #0\n\t" /* Linux/m68k system call */
	142	"tstl %0\n\t" /* child or parent */
	143	"jne 1f\n\t" /* parent - jump */
	144	#ifdef CONFIG_MMU
145	"lea %%sp@(%c7),%6\n\t" /* reload current */
146	"movel %6@,%6\n\t"
147	#endif
148	"movel %3,%%sp@-\n\t" /* push argument */
149	"jsr %4@\n\t" /* call fn */
150	"movel %0,%%d1\n\t" /* pass exit value */
151	"movel %2,%%d0\n\t" /* exit */
152	"trap #0\n"
153	"1:"
154	: "+d" (retval)
155	: "i" (__NR_clone), "i" (__NR_exit),
156	"r" (arg), "a" (fn), "d" (clone_arg), "r" (current),
157	"i" (-THREAD_SIZE)
158	: "d2");
159
160	pid = retval;
161	}
162
163	set_fs (fs);
164	return pid;
165	}
166	EXPORT_SYMBOL(kernel_thread);
167
168	void flush_thread(void)
169	{
170	current->thread.fs = __USER_DS;
171	#ifdef CONFIG_FPU
172	if (!FPU_IS_EMU) {
173	unsigned long zero = 0;
174	asm volatile("frestore %0": :"m" (zero));
175	}
176	#endif
177	}
178
179	/*
180	* "m68k_fork()".. By the time we get here, the
181	* non-volatile registers have also been saved on the
182	* stack. We do some ugly pointer stuff here.. (see
183	* also copy_thread)
184	*/
185
186	asmlinkage int m68k_fork(struct pt_regs *regs)
187	{
66d857b0	188	#ifdef CONFIG_MMU
fde39441	189	return do_fork(SIGCHLD, rdusp(), regs, 0, NULL, NULL);
1da177e4	190	#else
fde39441	191	return -EINVAL;
1da177e4	192	#endif
fde39441 GU	193	}
	194
	195	asmlinkage int m68k_vfork(struct pt_regs *regs)
	196	{
	197	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, rdusp(), regs, 0,
	198	NULL, NULL);
	199	}
	200
	201	asmlinkage int m68k_clone(struct pt_regs *regs)
	202	{
	203	unsigned long clone_flags;
	204	unsigned long newsp;
	205	int __user parent_tidptr, child_tidptr;
	206
	207	/* syscall2 puts clone_flags in d1 and usp in d2 */
	208	clone_flags = regs->d1;
	209	newsp = regs->d2;
	210	parent_tidptr = (int __user *)regs->d3;
	211	child_tidptr = (int __user *)regs->d4;
	212	if (!newsp)
	213	newsp = rdusp();
	214	return do_fork(clone_flags, newsp, regs, 0,
	215	parent_tidptr, child_tidptr);
	216	}
	217
	218	int copy_thread(unsigned long clone_flags, unsigned long usp,
	219	unsigned long unused,
	220	struct task_struct * p, struct pt_regs * regs)
	221	{
	222	struct pt_regs * childregs;
	223	struct switch_stack * childstack, *stack;
	224	unsigned long *retp;
	225
	226	childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;
	227
	228	childregs = regs;
	229	childregs->d0 = 0;
	230
	231	retp = ((unsigned long *) regs);
	232	stack = ((struct switch_stack *) retp) - 1;
	233
	234	childstack = ((struct switch_stack *) childregs) - 1;
	235	childstack = stack;
	236	childstack->retpc = (unsigned long)ret_from_fork;
	237
	238	p->thread.usp = usp;
	239	p->thread.ksp = (unsigned long)childstack;
	240
	241	if (clone_flags & CLONE_SETTLS)
	242	task_thread_info(p)->tp_value = regs->d5;
	243
	244	/*
	245	* Must save the current SFC/DFC value, NOT the value when
	246	* the parent was last descheduled - RGH 10-08-96
	247	*/
	248	p->thread.fs = get_fs().seg;
	249
	250	#ifdef CONFIG_FPU
	251	if (!FPU_IS_EMU) {
	252	/* Copy the current fpu state */
	253	asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory");
	254
	255	if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2]) {
	256	if (CPU_IS_COLDFIRE) {
257	asm volatile ("fmovemd %/fp0-%/fp7,%0\n\t"
258	"fmovel %/fpiar,%1\n\t"
259	"fmovel %/fpcr,%2\n\t"
260	"fmovel %/fpsr,%3"
261	:
262	: "m" (p->thread.fp[0]),
263	"m" (p->thread.fpcntl[0]),
264	"m" (p->thread.fpcntl[1]),
265	"m" (p->thread.fpcntl[2])
266	: "memory");
267	} else {
268	asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t"
269	"fmoveml %/fpiar/%/fpcr/%/fpsr,%1"
270	:
271	: "m" (p->thread.fp[0]),
272	"m" (p->thread.fpcntl[0])
273	: "memory");
274	}
275	}
276
277	/* Restore the state in case the fpu was busy */
278	asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0]));
279	}
280	#endif /* CONFIG_FPU */
281
282	return 0;
283	}
284
285	/* Fill in the fpu structure for a core dump. */
286	#ifdef CONFIG_FPU
287	int dump_fpu (struct pt_regs regs, struct user_m68kfp_struct fpu)
288	{
289	char fpustate[216];
290
291	if (FPU_IS_EMU) {
292	int i;
293
294	memcpy(fpu->fpcntl, current->thread.fpcntl, 12);
295	memcpy(fpu->fpregs, current->thread.fp, 96);
296	/* Convert internal fpu reg representation
297	* into long double format
298	*/
299	for (i = 0; i < 24; i += 3)
300	fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) \|
301	((fpu->fpregs[i] & 0x0000ffff) << 16);
302	return 1;
303	}
304
305	/* First dump the fpu context to avoid protocol violation. */
306	asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory");
307	if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2])
308	return 0;
309
310	if (CPU_IS_COLDFIRE) {
311	asm volatile ("fmovel %/fpiar,%0\n\t"
312	"fmovel %/fpcr,%1\n\t"
313	"fmovel %/fpsr,%2\n\t"
314	"fmovemd %/fp0-%/fp7,%3"
315	:
316	: "m" (fpu->fpcntl[0]),
317	"m" (fpu->fpcntl[1]),
318	"m" (fpu->fpcntl[2]),
319	"m" (fpu->fpregs[0])
320	: "memory");
321	} else {
322	asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0"
323	:
324	: "m" (fpu->fpcntl[0])
325	: "memory");
326	asm volatile ("fmovemx %/fp0-%/fp7,%0"
327	:
328	: "m" (fpu->fpregs[0])
329	: "memory");
330	}
331
332	return 1;
333	}
334	EXPORT_SYMBOL(dump_fpu);
335	#endif /* CONFIG_FPU */
336
337	/*
338	* sys_execve() executes a new program.
339	*/
340	asmlinkage int sys_execve(const char __user *name,
341	const char __user const __user argv,
342	const char __user const __user envp)
343	{
344	int error;
345	char * filename;
346	struct pt_regs regs = (struct pt_regs ) &name;
347
348	filename = getname(name);
349	error = PTR_ERR(filename);
350	if (IS_ERR(filename))
351	return error;
352	error = do_execve(filename, argv, envp, regs);
353	putname(filename);
354	return error;
355	}
356
357	unsigned long get_wchan(struct task_struct *p)
358	{
359	unsigned long fp, pc;
360	unsigned long stack_page;
361	int count = 0;
362	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
363	return 0;
364
365	stack_page = (unsigned long)task_stack_page(p);
366	fp = ((struct switch_stack *)p->thread.ksp)->a6;
367	do {
368	if (fp < stack_page+sizeof(struct thread_info) \|\|
369	fp >= 8184+stack_page)
370	return 0;
371	pc = ((unsigned long *)fp)[1];
372	if (!in_sched_functions(pc))
373	return pc;
374	fp = (unsigned long ) fp;
375	} while (count++ < 16);
376	return 0;
377	}